A new study found that schools that strictly adhered to masking guidelines saw dramatically lower community transmission of COVID-19 compared with schools with limited or no masking policies.
Schools with strong masking rules saw up to 87% less transmission compared with schools that did not strictly adhere to masking guidelines.
The study is believed to be the first of its kind to compare in-school COVID-19 spread from a large population of American schools. It was conducted by the ABC Science Collaborative and published in the journal Pediatrics.
The study included 61 school districts, more than 3,000 schools, and more than 1.1 million students and adults from across nine states, according to Duke University, which released the findings and is a member of the collaborative.
"The results of this study clearly show that universal masking reduces school transmission of COVID-19 when compared to optional masking, a finding that is consistent with earlier data," said Dr. Danny Benjamin, co-chair of the ABC Science Collaborative and professor in the Department of Pediatrics at Duke University School of Medicine. "As more students have returned to school, masking and vaccination of children 5 years and older have remained the most practical and effective mitigation strategies to keeping students healthy and learning in-person."
In addition to the findings, the collaborative published a calculator that parents and policymakers can use to guide decisions about when to install, or when to remove masking regulations.
"Where they can say, 'OK, here's the size of my district. Here's how many cases are going on in my county right now. This is how much COVID we are going to give to the community if we mask versus if we don't mask.'"
This can be a crucial tool to slow the spread of COVID-19, any of its variants, or any new respiratory virus, before it gets out of control. Importantly, this can help schools maintain in-person instruction, even if another surge happens.
"Maintaining in-person instruction is critical for children," said Dr. Kanecia Zimmerman, co-chair of the ABC Science Collaborative and associate professor of pediatrics at Duke. "Providing districts with the ability to monitor transmission data in real time and in response to changing policies allows them to shape their mitigation efforts during an evolving pandemic.
